Preheat the oven to 350F. Line several cupcakes pans with paper liners; set aside.

Prepare the strawberry cupcakes. In a large bowl, cream together the butter and sugar until light and fluffy. Add the eggs, vanilla and strawberry extract. Cream together until smooth. Pour in the milk, add the diced strawberries and strawberry preserves; whisk the mixture until smooth. In a separate bowl, combine the dry ingredients: flour, salt and baking powder. Add the dry ingredients into the cake batter and whisk only until combined.

Using a scoop, fill the cupcake liners almost full. Bake the cupcakes in a preheated oven for 30 to 35 minutes, or until edges are golden brown and a toothpick inserted into the center comes out clean. Allow the cupcakes to cool for about 5 minutes in the pan, then remove onto wire rack to cool completely.

Prepare the basil buttercream. Place the basil and 2 cups confectioner's sugar into a food processor. Make sure the basil is dry! Pulse the leaves and sugar together until a sandy, crumbly mixture forms; set aside. Place the softened butter into a mixer bowl and whisk on high speed for 5 to 7 minutes until the butter is light and fluffy.

To the butter, add the remaining 2 cups confectioner's sugar, vanilla, salt and optional green food coloring. Add the basil mixture. Whisk on high speed for a few minutes until a light and fluffy buttercream forms. Transfer buttercream into a pastry bag ( I used tip #847) and frost cooled cupcakes. Garnish with fresh strawberries, if desired.

Keep cupcakes refrigerated in an airtight container. Remove from the refrigerator an hour or two before serving to allow the frosting to soften.